PMC42, a novel model for the differentiated human breast

Cultured human breast carcinoma cell lines are important models for investigating the pathogenesis of breast cancer. Their use, however, is limited because of loss of expression of breast-specific markers and the development of a dedifferentiated phenotype after continuous culture. PMC42 is a unique human breast carcinoma line, previously shown to express secretory and myoepithelial markers. We have induced PMC42 cells to form hollow organoids in culture, similar to in vivo breast structures, using a combination of hormones including estrogen, progesterone, dexamethasone, insulin, and prolactin in combination with a permeable extracellular matrix. The organoids comprised polarized cells located around a central lumen. Expression of β-casein was demonstrated in cells within organoids using reverse transcriptase-polymerase chain reaction, Western blot analysis, and confocal immunofluorescence. In this in vitro system, milk-specific gene expression was induced through hormone and matrix interactions which may be similar to those operating in vivo. PMC42 is a novel model for investigations into the molecular mechanisms of carcinogenesis and differentiation in the human breast.

Problem-based learning and masculinities : unique opportunities for Mr. Fix It? Well, maybe

I watched a smoker of 30 years being admitted to the Coronary Care unit following an acute Myocardial Infarction (heart attack). The message from the male clinician was simple, accurate, but somewhat behaviourist: " the death of part of your heart muscle is the result of your smoking, if you don’t stop smoking the damage will continue and you will die." A global, proactive and humanistic consultation demonstrating an understanding of the man’s addiction to a legal and accessible drug and illuminating prevention strategies may have been more appropriate. Maybe the interaction was about competing masculinities, the risk taker and the problem solver. The irony? As I left the hospital that night I observed the same clinician strategically positioned in a secluded hospital doorway drawing heavily on a cigarette. Hypocrite? No, invincible late 20’s male? Maybe. Smoking was someone else’s problem – at least today.

In my 16 years as a clinician such scenarios are common. Clinical practice based predominantly on problem solving potentiates hegemonic masculine approaches to treating men in clinical practice, often justified by limited health resources and increasing patient acuity. Ironically, Problem-based Learning (PBL) curriculums commonly used in health sciences higher education encourages, nurtures and rewards such problem solving approaches. As a teaching academic with current clinical practice it occurs to me that health science education and PBL has an opportunity if not obligation to empower clinicians to establish holistic approaches to male health presentations.

This paper explores the interconnections of Problem-based Learning (PBL) curriculums, health promotion, male nurses’ health-related behaviours and the implications and specificities of masculinity. The pilot study offers an insight into the perceptions of three male nurses that completed undergraduate nursing studies in PBL curriculums. The data obtained introduces some connections that could be illuminated by further research.

Recolonisation of lagoon of islands, Tasmania, by Baumea Arthrophylla: the first step in regeneration of a unique ecosystem?

Lagoon of Islands was a unique ecosystem. Damming the lagoon in 1964 caused the decline of the ecosystem, destroying the original vegetation and, eventually, rendering the lagoon eutrophic. While this took place the lagoon was colonised by a macrophyte not previously noticed in the lagoon. In an effort to restore acceptable water quality, restoration of macrophyte cover was encouraged by hydrological manipulation. Recent investigations have revealed that one of the original dominant macrophyte species is recolonising the lagoon, creating an alternative management option for the lagoon.

Planar receiver placement for unique emitter localization for indoor applications

This paper investigates two independent approaches to verify the necessary and sufficient condition to guarantee a unique solution for a passive emitter localization system based on time difference of arrival measurements from an
array of sensors.

Unique marine Permian-Triassic boundary section from Western Australia

A unique marine Permian-Triassic boundary section containing rich oil source rocks has been continuously cored in a petroleum borehole from the Perth Basin of Western Australia. Such sequences, which provide a biostratigraphic and environmental record at the time of the largest extinction event of the past 500 million years, are globally rare, and this is the first to be documented in Australia. Throughout geological history there have been periods of global marine anoxia that commonly resulted in the widespread deposition of petroleum source rocks, most notably in the mid-Cretaceous and Late Jurassic. An apparent paradox is that, previously, source rocks have not been recognised in association with the Permian-Triassic boundary, despite widespread marine anoxia at this time. The Perth Basin source rocks contain abundant and unusual biomarkers, apparently related to the highly specialised and limited biota that flourished in the aftermath of the end-Permian extinction event. Local conditions may have favoured source-rock development, either due to higher productivity resulting from coastal upwelling or through enhanced preservation under strongly anoxic conditions.

Modulation of tumor necrosis factor receptors 1 and 2 in chronic hepatitis B and C: The differences and implications in pathogenesis

Tumor necrosis factor (TNF) plays a role in the pathogenesis of chronic hepatitis B (CHB) and chronic hepatitis C (CHC). The difference in the cytokine responses between hepatitis B virus (HBV) and hepatitis C virus (HCV) infections may have implications in the pathogenesis of these diseases. We performed a comparative study to examine the possible differences in the TNF-TNF receptor (TNFR) response between CHB and CHC. We studied the cytokine levels of 38 patients with CHB, 40 patients with CHC and 9 patients with dual hepatitis B and C, and compared them with the baseline levels of 12 healthy controls. The plasma levels of TNF-, interferon-, interleukin (IL)-2, IL-4, IL-10 and soluble TNFR-1 and 2 (sTNFR-1 and 2) were quantified by enzyme-linked immunosorbent assays. The expression of TNFR-1 and 2 in liver tissues was examined in 30 cases of CHB and 15 cases of CHC by semiquantitative reverse transcription polymerase chain reaction. The results showed that sTNFR-1 levels correlated with liver inflammation in all patients, whereas this correlation was not found with sTNFR-2 or other cytokines. Liver inflammation indicators were higher in HCV RNA+ than in HCV RNA– CHC. Most significantly, sTNFR-1 levels correlated with liver inflammation in CHB, but not in CHC. However, the expression of TNFR-1 and 2 in liver was similar between CHB and CHC. These findings suggest that the TNFR signal transduction pathway is modulated differently in HBV and HCV infection.

Changes in bacterial concentration in the liver correlate with that in the hepaticojejunostomy after bile duct reconstruction: implication in the pathogenesis of postoperative cholangitis

Postoperative cholangitis is a frequent and unpredictable complication of unknown etiology following bile duct reconstruction (BDR), particularly for biliary atresia. This study was undertaken to correlate the growth of bacteria in the hepaticojejunostomy with that in the liver after BDR. Quantitative bacterial culture was done on the specimens taken from the liver and from the hepaticojejunostomy at 1 week (group 1, n = 7), 1 month (group 2, n = 7), and 2 months (group 3, n = 7) following BDR with Roux-en-Y hepaticojejunostomy in piglets after 2 weeks of common bile duct ligation. The histological examination of the liver and the hepaticojejunostomy, as well as serial monitoring of hemogram and liver function tests, were performed to correlate the findings with the bacterial concentration of the liver and the hepaticojejunostomy following BDR. The bacterial concentration of the hepaticojejunostomy, expressed as log10 colony-forming units per gram (log10 CFU/g) of the hepaticojejunostomy, showed a progressive decrease from 8.38 ± 1.36 in group 1, 7.07 ± 2.54 in group 2, to 3.56 ± 1.31 in group 3 (p = 0.001). The log10 CFU/g of the liver also showed a progressive decrease from 5.02 ± 1.59 in group 1, 3.16 ± 1.56 in group 2, to 2.19 ± 1.09 in group 3 (p = 0.006). There was a significant positive correlation of the log10 CFU/g of the liver (n = 21) with that of the hepaticojejunostomy (n = 21) following BDR (r = 0.600, p = 0.004). Most of the infectious pathogens isolated from the liver were also isolated from the hepaticojejunostomy. The changes in hemoglobin, bilirubin, albumin, and ammonia significantly correlated with the changes of the bacterial concentration of the liver. The results of the study suggests that hepatic bacterial proliferation after BDR is significantly affected by microbial overgrowth in the bilioenteric anastomosis and is associated with deteriorated liver function and hemogram.

Maternity waiting homes in Southern Lao PDR : the unique 'silk home'

The concept of maternity waiting homes (MWH) has a long history spanning over 100 years. The research reported here was conducted in the Thateng District of Sekong Province in southern Lao People’s Democratic Republic (PDR) to establish whether the MWH concept would be affordable, accessible, and most importantly acceptable, as a strategy to improve maternal outcomes in the remote communities of Thateng with a high proportion of the population from ethnic minority groups. The research suggested that there were major barriers to minority ethnic groups using existing maternal health services (reflected in very low usage of trained birth attendants and hospitals and clinics) in Thateng. Unless MWH are adapted to overcome these potential barriers, such initiatives will suffer the same fate as existing maternal facilities. Consequently, the Lao iteration of the concept, as operationalized in the Silk Homes project in southern Lao PDR is unique in combining maternal and infant health services with opportunities for micro credit and income generating activities and allowing non-harmful traditional practices to co-exist alongside modern medical protocols. These innovative approaches to the MWH concept address the major economic, social and cultural barriers to usage of safe birthing options in remote communities of southern Lao PDR.

Bamboo fibres and their unique properties

This paper collates the different properties of bamboo fibres as claimed by bamboo fibre and product manufacturers. The available information suggests that bamboo fibres have unique properties such as excellent appearance and feel, natural antibacterial, UV-shielding and moisture-controlling characteristics. Hence bamboo fibres provide a very promising alternative to other natural fibres by virtue of their novel properties. However, those properties may largely depend on the manufacturing process, which is not widely disclosed. Moreover, common manufacturing process may require the use of a large amount of chemicals and hence further process development may be required in order to make the product truly eco-friendly. It is identified that the data of those unique properties rarely appear in scientific journals and the validity of those claims can be speculative. Therefore, there is a strong need for non-biased scientific research and evaluation on the unique properties of bamboo fibres.